Old-school spy

Kim Philby was widely respected, yet, like others, he betrayed his country. Researching a thriller on the British secret service led William Boyd to ask how such a privileged Englishman could become such a successful Soviet agent

"Very limited intelligence ... by and large pretty stupid, some of them very stupid." Such was a new recruit's opinion of his colleagues in the British secret service at the beginning of the second world war. He went on, unsparingly: "There were the metropolitan young gentlemen whose education had been expensive rather than profound and who were recruited at the bars of White's and Boodles, and there were the ex-Indian policemen ... Neither class had much use for ideas. The former had seldom heard of them; the latter regarded them as subversive."

I spent many months last year researching the British secret service for my novel Restless - the story of a young woman working in the lower echelons of the British espionage business - and I found this dry and acerbic analysis particularly helpful and revealing. Not least because this was the organisation that had admitted into its ranks at least five double agents for the Soviet Union: Guy Burgess, Donald Maclean, John Cairncross, Anthony Blunt and the "super spy" Kim Philby, whose near-effortless rise through the secret-service hierarchy resulted in him being groomed, postwar, for the ultimate top job - that of "C" itself. It would have been an unrivalled coup for Moscow to have their man running the British secret services. And it very nearly came off.

In the course of writing the novel I became very curious about this covey of British double agents and what united them, apart from their betrayal of their country. All were middle class or upper-middle class, all well educated with solid professional careers in the great institutions of the state. They were members of "the establishment" in every degree - their background, their ostensible values, their speech, their clubs, their dress, their pastimes and pleasures. There was nothing on the surface to distinguish them from the thousands of other privileged, Oxbridge-educated young men working in the Foreign Office or the diplomatic service or the BBC. Yet each chose to become a traitor.

One can understand how in the 1930s, when these agents were first recruited by the Soviets, the ideological appeal of communism presented the only real alternative to the seemingly inexorable rise of fascism in Europe. Yet the more I looked at these men and read about their double lives, considered their fallibilities and their anxieties (Burgess and Maclean in particular), their luck and their unremarked incompetence (Philby excepted) - I began to feel that ideological zeal simply couldn't explain their many years of successful and fatal duplicity. There had to be some other motivation other than the allure of communism - especially after the devastating shock of the Nazi-Soviet pact of 1939. Once Stalin and Hitler became allies, only the most perverse reasoning could maintain that there was one true enemy of fascism and that it was Soviet Russia. The tortuous double-think of the Communist Party of Great Britain (CPGB) is both revealing and risible in this regard. The Daily Worker, the party's newspaper, had been virulently pacifist and anti-Nazi, but after the 1939 pact all criticism of Hitler virtually ceased in the paper. Then, when Hitler invaded Russia in June 1941, the CPGB became virulently anti-Nazi again. No person of intelligence could take such policy about-turns seriously.

Furthermore, these British traitors both lived in and flourished in a democratic society, each one benefiting from the privileges offered to its educated elite. They were not hounded or embittered, nor victims of repression or state corruption, nor thwarted in ambition, blocked at every turn - so why did they become traitors?

The case of Kim Philby is perhaps the most interesting. Philby was a man universally liked, a highly respected professional - competent and industrious, decorated after the war - and a charming and amusing companion. His wife regarded him as a "divine husband" and classed their marriage as "perfect". He existed at the highest levels of the secret service for 10 years, between 1941 and 1951, without attracting the slightest suspicion. Hugh Trevor-Roper (the author of the caustic judgment on his colleagues above) knew Philby during the war and described him as "an exceptional person: exceptional by his virtues, for he seemed intelligent, sophisticated, even real".

In 1951, after the flight of Burgess and Maclean to Moscow, Philby was obliged to resign from the service, to the regret of his colleagues, because of his close association with Burgess, a friendship that he refused to disown. Even this was regarded as a symbol of his fundamental decency and good fellowship. It was not held against him and he was reintroduced to the service after some years in a minor role (in Beirut) before eventually fleeing to Moscow in 1963 - possibly because a Soviet defector was about to reveal his identity.

No one really knows how many deaths and imprisonments Philby was responsible for. The number is probably in the hundreds. For example, British agents and couriers sent to Albania and Ukraine to foment anti-communist revolution after the war were routinely intercepted and executed thanks to Philby's advance warnings. In Washington in the late 1940s he passed on all secret material that crossed his desk to the Russians - most usefully analysis of America's nuclear capability. One can argue that Philby's information was instrumental in the prosecuting of the Korean war and the Cuban missile crisis. He was an extremely effective and important double agent.

Trevor-Roper was clearly baffled (as baffled as I was) when he came to consider Philby's character and to try to come to terms with the fact that his former friend was a traitor. He wrote a series of articles in the 1960s, after Philby's flight and resurfacing in Moscow, analysing the affair. How could someone like Philby have been such a successful traitor? How had everybody trusted him all these years? How could he be so loyal to a brutal and disgusting tyrannical state - Stalin's Russia? Seeking answers, Trevor-Roper eventually came up with the somewhat high-flown thesis that communism had created in Philby a form of "death of the mind", that he "had drunk from the drugged chalice of that secret church". I just don't buy this, not least because Philby was not alone. Are we to assume that the other four British traitors had also sipped at this "drugged chalice" and had undergone this "death of the mind"? Perhaps one might - just - but surely not all five. I think the answers to this particularly British state of affairs lie elsewhere.

Seeking explanation, I created in my novel a Philby-style traitor, but one who is never exposed as Philby was, and in so doing I had to consider the reasons why a character so favoured by fortune in his native country should strive so diligently to betray it. There are, it seems to me, two plausible reasons that explain the behaviour of these British traitors and Philby in particular. The first can be summed up as "once a spy, always a spy". Even if ideological zeal takes you into the double-agent profession it is very difficult, once that zeal dies, or is replaced by clearer, more pragmatic vision, to get out of it. Not only is it a question of potential exposure (it's very hard to resign as a traitor) but it becomes, in other words, a habit of mind, a double life that seems an almost natural one to lead.

This explains someone like Anthony Blunt - perhaps the least lethal of the Cambridge spies, but the one who rose to a position of extraordinary eminence in public life that is almost incredible: keeper of the queen's pictures, a knighthood, head of the Courtauld Institute, an internationally recognised art authority and collector and a world expert on Poussin. Trying to comprehend the level of Blunt's self-knowledge as he accepted these successive honours is almost impossible. It reveals something almost freakish about him: this is a man who took enormous pains to betray his country, yet he was prepared to accept every honour it would bestow on him. Blunt's case, in retrospect, is almost surreal. With Philby, there seemed some more subtle and corrupting rationale at work.

There are many reasons why people betray their country. One is revenge, and a subcategory or corollary of revenge is "hate". Wilful betrayal of your country implies some sort of hatred of your country, and in the example of Blunt we have an insight into Philby's extraordinary career and personality.

I realise that we now enter the area of informed speculation, but Trevor-Roper gave another, inadvertent clue when he referred to Philby's "unquestioning, all-absorbing egotism which guided him in all his actions". Here is an explanation that holds more water than the "death of the mind". Philby's betrayal becomes more plausible and comprehensible if one regards it as a form of sweet and pure egomania. The fact that he was being groomed to become head of the secret service just adds extra gloss to the nature of that betrayal. Philby was outsmarting and had outsmarted everybody: it was the very nature of his continued success, the respect he engendered and the overt devotion and admiration of his colleagues that fuelled and drove his double life. I would argue that it had nothing to do with idealism at all.

But there is still one further impulse that, I believe, explains the collective betrayals of these privileged, intelligent men. Britain in the 1930s was both rich and globally powerful. These five double agents found themselves members of its favoured classes at the heart of the English elite, at the very centre of establishment supremacy and influence. As these men looked around them, what did they see? Did they like what they saw? Did they like what they were? The writer Frederic Raphael has observed that "When Britain was rich and powerful, a man might believe himself devoted to either forwarding or altering her purposes." My hunch is that the five Cambridge spies all decided to take the latter course.

Philby himself alluded obliquely to this when he was interviewed by a British newspaper after his defection to Moscow in 1963. He said he regarded himself as "wholly and irreversibly English and England as having been perhaps the most fertile patch of earth in the whole history of human ideas". Asked why he then betrayed this wonderful country, he said that he held a "humane contempt" for "certain temporary phenomena that prevented England from being herself".

This is the crucial admission explaining Philby's treason and, moreover, the casual use of "England" and "English" is very revealing - the unreflecting language of the establishment. Here is the clue to the swagger and sheer aplomb of Philby's sustained and astonishingly successful betrayal. He calls it "humane contempt", but I think "contempt" will do nicely. With his impregnable self-assurance, the egomaniac contemplates the rich and sacrosanct world he's been born into (let us recall Trevor-Roper's own harsh judgment of his peers and superiors) and finds he has nothing but contempt for it. In such circumstances, sometimes it is just as easy to hate your country as it is to love it.

What is a man like Kim Philby to do in such a situation, as he looks around him and senses his contempt burgeoning? What options exist? Exploitation, denial, resignation, some form of flight - or betrayal? Philby and his fellow privileged traitors made their choice.

· William Boyd's new novel, Restless, is published this month by Bloomsbury, price £17.99